The present invention relates to working additively manufactured parts, and in particular, to melting and re-solidifying additively manufactured parts.
Additive manufacturing is becoming increasingly popular as a means for manufacturing parts with complex shapes. Additive manufacturing allows a part to be manufactured layer-by-layer, which allows complex design features to be included in the part design when it was previously impossible. Additive manufacturing processes generally include the following steps. First, a three-dimensional model of the part is created using computer software. The computer model is then sliced into a plurality of layers. Information about the first layer is then transmitted to an additive manufacturing machine. The additive manufacturing machine then builds the first layer of the part. Information about the second layer is then transmitted to the additive manufacturing machine and the additive manufacturing machine builds the second layer of the part on top of the first layer. This process continues layer-by-layer to generatively build a part.
One challenge that is faced when using additive manufacturing processes is controlling the surface finish and crystallization of the part. The surface finish of an additively manufactured part typically has an average surface roughness Ra between 175 microinches (4.4 micrometers) and 600 microinches (15.2 micrometers). This surface finish is unsuitable for parts that are used as aerodynamic parts, for instance vanes located in a gas turbine engine. Rough aerodynamic surfaces increase turbulence and decrease the effectiveness of the aerodynamic parts. Further, it is difficult to control the overall crystallization of additively manufactured parts due to the layer-by-layer construction of the parts. Crystallization of a part can affect the mechanical, optical, and electrical properties of the part.